Whey product derived from milk and process of producing same



Patented June 5, 1951 WHEY PRODUCT DERIVED FROM MILK AND PROCESS OF PRODUCING SAME Paul Francis Sharp, Piedmont, David D. Peebles, Hillsborough, Le Roy Raymond Hawk, San Francisco, and Arthur M. Besemer, Alameda, Calif., assignors to Golden State Company, Ltd., San Francisco, Calif a corporation of Delaware N Drawing. Application January 20, 1947, Serial No. 723,212

-13 Claims.

This application is a continuation-in-part of our co-pending application Serial No. 510,374, filed November 15, 1943, which has now abandoned.

This invention relates to a new and useful product derived from milk, and more particularly to a processed whey product which possesses certain desirable properties making it particularly useful as a substitute for milk in the manufacture of bread and like products.

This invention also relates to a novel process by which the product of this invention may be produced.

It has been the practice for a substantial period to utilize milk as an ingredient in the manufacture of bread. It is well known in the baking industry, that when milk is employed in preparing bread dough, the finished bread possesses certain desirable properties such as an improved keeping quality, good volume for the ingredients employed, and good toasting characteristics.

It has long been the purpose of investigators in this art to find a satisfactory substitute for milk, however, since it would be highly advantageous to be able to use a less expensive ingredient which would, nevertheless, give the same properties to the finished product as does milk. Many attempts have been made to use whey as such as a substitute since great quantities of whey are obtained as a by-product in the manufacture of cheese, casein, and the like. Generally speaking, however, these attempts have failed because it has been found that bread produced with unprocessed whey results in loaves having overall poor quality.

For instance, it has been found that the use of unprocessed whey produces bread dough having poor moisture absorption and poor mixing characteristics and also produces finished loaves of bread which are characterized as having poor texture, poor body or crumb, poor moisture retention properties and insufficient volume for the quantity of ingredients employed. Furthermore, the lower moisture absorption property prevents the incorporation, during the dough-making procedure, of that amount of moisture requisite for good yield. In addition, the lower moisture retention property of the bread permits a rapid loss of the already reduced amount of moisture previously absorbed in the dough, and the moisture content of the bread is therefore quickly reduced below that amount requisite for best keeping qualities.

It is therefore an object of the present invention to provide a new and improved processed whey which is free from the above-stated objections and which can be used in the baking industry as a substitute for milk, since it imparts to the finished bread good moisture retention properties and the other characteristics considered necessary for overall good quality which are usually obtained only by the use of milk.

It is a further object of this invention to provide a process by which the novel product of this invention may be produced.

These and other objects not specifically enumerated will appear to those skilled in this art from an understanding of the following disclosure, which is given by way of illustration.

In carrying out the method of this invention, the whey being processed, which may be ordinary whey or whey to which vegetable, yeast, or animal protein has been added, is subjected to a number of steps including concentration, adjustment of its pH where necessary, adjustment of the calcium content, and a high heat treatment, as fully set forth below. It is critical to the results of this invention that the pH and calcium content be adjusted prior to the high heat treatment, but it is to be understood that such adjustments can be made either before or after the concentrating step. In certain instances it may be preferred to adjust either the acidity or the calcium content, or both when necessary, prior to the concentration step, while in other instances the reverse order of treatment may be preferred. Accordingly, the invention is not to be limited in this respect and the claims are to be construed as covering either order of practice irrespective of the order in which these steps appear in the claims.

When the protein content of the Whey is increased by the addition of small amounts of non-milk proteins, such addition generally should not exceed 20% by weight on a dry basis. Such addition may be made at any time prior to the high heat treatment. If the protein is such as to readily take on colloidal character within the pH range of 6.0 to 6.5, then the usual procedure is that of adding the protein material prior to the pH adjustment step.

The vegetable protein, for example, protein from soybean, peanuts and the like, may be introduced in any one of a number of ways. Soybean flour may be added to the whey without any pretreatment. 011 the other hand soybean protein may be prepared by the following pre-treatment. A suspension of soybean flour in water is formed and the protein precipitated therefrom by addition of acid. This precipitated protein may be separated from the suspension and added as a 3 homogeneous component or the whole mixture of soybean flour suspension, acid, and precipitated proteinmay be added to the whey.

The fortification of whey with protein, has the effect of simplifying the drying operation. The eiTect upon the final product is tofurther improve and allow greater control over such dough characteristics as Water absorption and speed of aging. The addition oi such proteins as soybean and yeast also improve the flavor and nutritional value of the product.

In carrying out the pH adjustment step, a suitable neutralizing agent such as an alkali or an alkaline earth hydroxide is added to the whey. Sodium hydroxide, potassium hydroxide, ammonium hydroxide or calcium hydroxide, for'instance, may be added in a quantity sufficient to adjust the pH of the whey being processed, to a value such that a sample of that whey, when brought to a solids concentration of 6%, will have a EI-I of approximately 6.0 to 6.6. It should be notedthatall values of the pH given herein, including the'values stated in the claims are likewise "*g'iven'with referenceto'a sample of the-whey being processed, after that sample has been brought to a solids-concentration. It is not desirable to :go beyond neutrality or approximately a pH of 7.0 whena djusting-the-pl-I because of the deleterious efiect upon the -nitrogen bearing protein "compounds. If the Whey being'processed is a "-sweet whey, y-ihich usually has a pH in the neighborhood of 6. 4, itis of course understood thatdittle-if any pH adjustment need be carried out on the other hand,the quantity of neu- "tralizing fagent employedwill vary considerably 'accordingtothe initial acidity of a sour whey being treated. for this reason this invention is -notto be-li'mitedtoany particular quantity, pro- :videtl-only thatin-all'cases the quantity of neutralizing-agentshould be that quantity that will adjust'the -pH of the Whey to the desired value pointed-out above.

The step o'fa'djusting the calcium content of- -tlre"whey may becarried out by any one of a -'number*ofmethods'by which the calcium content, -measured as-calcium itself, is raised to a point --wher'e it constitutes from approximately 135% to approximately 3.0% by weight of the dry-solids 'of -whey. From 2.0% to 2.5% is an even more desirable range, with about 2.25% being-the optimumv-alue. Of the non-poisonous 'le'm'e'n-ts of group II of the-periodic table of eleinents,'ca1ciu'm' is the only element found that both develops thedesired thickening characteristic in the treated whey, and gives the treated "whey the properties described above that result in the iinproved baking properties of the dough to which the treated whey has been added.

Other-elements such as magnesium and strontium cause the treated'whey to exhibit the thickening "characteristic but wheys containing these ele- 1 merits have-not been found to be useful as a sub- 'stitute-for milk in-baking.

@n'e metho'do f adjustment of the calcium content is to add soluble orpartially soluble neutral 's'altsgsu'chas the soluble anhydride form of calcium sulfate, calcium phosphate, calcium --aceta-te, calcium lactate or calcium citrate to a 'whey-hav-ing'the proper pH which it may have While 4 concentration of the chloride ion inhibits the growth of yeast, and thereby afiects the breadmaking properties of the dough and the quality of the'finishedlproduct.

Another method is to use calcium hydroxide as the neutralizing agent. If the Whey being treated is markedly acid, for example, if it has a pH between 3.5 and 5.0, sufficient calcium may be added during the neutralizing step to reach the proper calcium'content. If, however, the pH is not too low, as for example, about 5.5, the amount of calcium added as a neutralizing hydroxide may not be suflicient to reach the proper 'calciu'mcontent level unless one exceeds a pH of 7. Under these circumstances, after neutralizing to the proper pH range, a neutral calcium salt is added to attain the proper calcium content.

It may sometimes be advantageous to add an acid salt of calcium such as mono or di-calcium phos'ph'ate sin'ce i-twould possess the additional property of influencing the yeast growth. When suchan'a'cid salt is usedhowever, allowance must be made for its effect on the pH in the neutralizing -step. Obviously, any combination of the above -meth'ods may be utilized as the circumstances permit.

. "Theconcentrating-step may be carried out by evaporation or-any other suitable concentrating procedure until the solids content of the whey has been materially increased, as for example, by c'o'n'centrating t0 apointwhere the solids content is from approximately 25% to approximately 55%. Preferably, however, the concentration "shouldbe from 35% to 50%. Any suitable evapor'ating equipmentmay beemployed and, if desired, the evaporation may be carried out in a number of stages. In such event, it is preferable to employ evaporating equipment such as the Peebles and Manning evaporator, disclosed in United-States Patent No. 2,090,985, and to con- -duct the final stages of evaporation under high 'vac'uum until the final concentration is increased try-somewhere between about 25%:and about 55% solids.

After the whey has been thus treated, the whey concentrate-is next subjected toa relatively high temperature treatment, as for example, to

-a temperature'within therange of approximately *200-degr'e'esi. to approximately 280 degrees F. (andipreferably in the neighborhood of 250 degreesTt'). This heat treatment is continued at s'u'chtemperature-for a period sufficient to attain -'production of a maximum quantity of insoluble solids determinableiby suitable known methods. The per-iod'tof heat treatment varies from approximately 'one half minute to approximately fifteen-minutes depending upon certain conditions. "In general the higher the calcium content and the higher the temperature, the shorter the holdin'g time required toattain the maximum quantity of insoluble solids. The presence of such 'insoluble solids maybe evidenced by the consistency-and appearance of a custardpud- "ding -andthe same may be'separated'by the use of a ce'ntrifuge, or the like.

The heat treatment may be carried out in any suitable equipment, 'such as that in which the Whey is heated by direct contact with steam, or, if desired, in-a heatexchanger which has a high velocity liquid flow and which is capable of rapidly heating the whey to the desired temperature.

As has been stated above, it has been found that as. a result of--the above-described treatments, "the whey -s'o processed possesses qualities of markedly superior character when used in bread dough as a substitute for milk, The treatment described, including the high heat treatment, in some way alters the whey constituents so as to impart to the whey the property of increasing the water absorption and retention properties of the bread-making materials. Dough prepared with whey which has been so treated consequently possesses water absorption and retention properties which compare favorably to those of dough prepared with milk as an ingredient. In addition, dough prepared from treated whey is free from any tendency to producebound loaves or loaves having insufficient volume for the ingredients employed, accompanied by poor texture and poor body or crumb. Bread thus produced is not only of excellent quality as a food but, in addition, has keeping qualities, and other characteristics comparable to those of bread produced with milk as an ingredient.

The whey product obtained as above described is a relatively inexpensive material which possesses desirable food properties and which can be used with highly successful results as an ingredient in various bread mixes in place of whole or skim milk. If desired, the product can be used in the form of a liquid concentrate or, if preferred, in the form of a dry stabilized powder. For instance, the procedure disclosed and claimed in applicant Paul F. Sharps copending application, Serial No. 697,954, entitled Process for Drying Solutions Containing Crystallizable Material and Product Produced Thereby, filed September 19, 1946, or any other method and means which may hereafter be devised and which successfully produces from the concentrate of this invention a satisfactory dry powder, may be employed.

This invention, therefore, does not extend to the subsequent treatments that may be employed for drying the same, nor is this invention to be restricted to any particular physical form of the final product, as all forms thereof can be satisfactorily employed in the baking industry. The wet concentrate or the dry whey may be added directly to the baking mix, for instance, or the dry powder may be mixed with water prior to the time it is introduced into the bread mix and the water suspension added to the other ingredients making up the mix.

The following examples further illustrate the invention.

Example 1 A cottage cheese whey having a pH of approximately 4.5 is first neutralized while being thoroughly agitated. This may be done by introducing into the whey a by weight suspension of lime in water in a quantity sufiicient to adjust the pI-I to approximately 6.5. This quantity of lime will produce a calcium content of approxi-- mately 2% on a dry solids basis.

The adjusted whey is next concentrated to a solids content of roughly 46% in a multiple effect evaporator. A temperature of approximately 115 degrees F. is preferably employed. This concentrate can be heated by a direct injection of steam and its temperature raised to approximately 250 degrees F. at which it is held for approximately 2 minutes with the result that a marked flocculation is apparent to the naked eye. The heated concentrate may then be spray dried to form a dry powder.

Although the amount may be varied, 6 pounds of this powder is normally used for each 100 pounds of flour in a baking formula. This amount of powder constitutes the equivalent amount of solids present in skim milk used in bread making by the standard formula. Bread prepared from the whey processed as described will have good dough characteristics, i. e. it will not be too sticky, it will have the proper water absorption and it will match the volume of bread prepared by the standard skim milk formula. This result is in marked contrast to the poor water absorption and roughly to volume obtained with untreated whey.

Example 2 A sweet whey having an original pH of approximately 6.5 may be adjusted as to calcium content by the addition with thorough agitation of a sufficient amount of the soluble anhydride form of anhydrous calcium sulfate, in the form of a 25% by weight slurry, to raise the calcium content to 2%.

This mixture may then be heat treated as. described in Example 1 and the treatment will give substantially the same results.

Example 3 The procedure outlined in Example 1 may be slightly modified to provide a third illustrative example. According to this example, protein may be added to the Whey concentrate after the same is removed from the multiple effect evaporator. For instance, 15% by weight, computed on a dry solids basis, of soy bean flour may be added to the concentrate and thereafter the mixture further treated in accordance with the procedure outlined in Example 1.

Bread prepared from the whey produced in accordance with this third example will have dough and baking characteristics similar to those of bread prepared with whey produced in accordance with Example 1, except for the fact that the product of this example will have a slightly higher water absorption property. This increase in the water absorption property provides a real advantage in that it permits the introduction initially of a large amount of water for the solids employed and in addition enhances the water retention properties. i

What is claimed is: l. The process of producing a product derived from milk which comprises, concentrating a whey having a pH of from 6.0 to 6.6 and a calcium content, computed on a dry solids basis, of between approximately 1.5% and 3.0 to a point where the solids content is from approximately 25% to approximately 55%, and thereafter heating the concentrated whey at a temperature from approximately 200 F. to 280 F. for a period suffi- .cient to produce insoluble edible proteinaceous material in quantity sufficient to impart a pudding-like consistency to the product.

2. The process of producing a product derived from milk which comprises, without reference to order, adjusting the pH of the whey to a value of from approximately 6.0 to 6.6, adjusting the calcium content, computed on a dry solids'basis, to between 1.5% and 3.0% by weight and concentrating the whey to a point where the solids content is from approximately 25% to approximately 55%, and thereafter heating the concentrated whey at a temperature from approximately 230 F. to 260 F. for a period sufficient to produce insoluble edible proteinaceous material in quantity suificient to impart a pudding-like consistency to the product.

3. The process of producing a product derived lifrom milkwhich comprises, without. reference 'to lorder,:adjustingthe pH of the whey -by introducing .into the whey a neutralizing agent in iquantity .sufiicient to bring the pH of said whey to a value of from approximately 6.0 to 36.6, ad-

;justing'the calcium content of the whey by introiducingicalcium asa salt in quantity sufficient to :bringflthe .calcium content, computed on a dry solidsbasis, to a -.value of from approximately 1.5% :to 13.0% 'and concentrating the whey .to a point where the solids content is from :approximately 25% to approximately 55%, and thereafter heating the concentrated whey at a term perature from approximately 230 F. to 260 F. for a per-iodsufiicient to produce insoluble edible proteinaceou's material in quantity sufficient to imparta pudding-like consistency to the product, :said period falling within the range of approximately one-halfminute tofifteen minutes.

4. The process of producing a product derived fromtmilk'which comprises, without reference to order, simultaneously adjusting the pH of the whey to between approximately 6.0.and 6.6 and the calcium content, computed on a dry solids basis, to between approximately 1.5% and 3.0 a by introducing into the whey having an initial pH in'the range of 3.5 to 5.0 a sufificient quantity ofcalcium hydroxide and concentrating the whey to a point where the solids content is from apto approximately 55%, and 1 proximately 25% thereafter heating the concentrated whey at a temperature from approximately 230 F. to 260 F.'-for a'period sufficient to produce insoluble edible protcinaceous material in quantity suiiicient to impart a pudding-like consistency to the prodnot, said period falling within the range of ap- ::proximately one-half minute to approximately f'fifteen minutes.

5. The process of producing a product derived ffrommilk which comprises, without reference to order, adjusting the pH of the whey by introducing into the whey calcium hydroxide and another .neutralizingagent in quantity sufiicient to bring the pH of said whey to a value of from approximately 6.0 to 6.6, adjusting the calcium content-computed on a dry solids basis, to between 1.5% and 3.0% by introducing a calcium salt and concentrating the-whey to a'point where thesolids content is from approx-imately'25% to :approximately 55%, and thereafter heating the concentrated whey at-a temperature from approximately 230 F.'to 260 F. for a period surficient toproduce insoluble edible proteinaceous .zmaterial in quantity sufiicient to impart a pudding-like consistency to the product, said period falling within the range of approximately one- -half minute to approximately fifteen minutes.

6. The process of producing a product derived from milk which comprises,without reference to order, adjusting the pH of .the'whey'by introducing ,into the whey a neutralizing agent in quantity sufficient to bring the pH of: said whey to a value of approximately '-6.5, adjusting the calcium content, computed on a dry solids ba is, .to between 20% and 2.5% by-introducing acalcium salt and concentrating the Whey to a point where the solids content is from approximately 25% to approximately 55%, and thereafter heatinglthe concentrated whey at atemperaturefrom approximately 230 F. to260 Frfor a period sufpficient to produce insoluble edible proteinaccous material in quantity suihcicnt to impart a pudding-like consistency:to the product.

7. The process of producinga product derived .from milk which comprises, withoutre-ference to order,..adjustingxthe. pH pfithe whey by introducing into the whey a neutralizingagent in :quantity sufficient to .bringthe pH of said whey to :a'yalue of from. approximately 6.0 to 6.6, adjusting the calcium content of the whey by introducing ;cal-

cium :as a salt in quantity sufficient ;to bringthe calcium content, computed on .a dry .solidsabasis,

to avalue of from approximately 2.25% andcon- 'centrating the whey .to a .point where the solids content isfrom approximately 25% :to approximately 55 %,.;and thereafter heating the concentrated whey ata temperature from approximate- .ly. 230 F. to 260 E..for a'period sufficient to produceinsolub'le edible proteinaceous:materialin quantity sufiicient to impart a pudding-like consistency to .the product.

v8. The process :of producing a product derived from 'milk which comprises, without reference to order, adjusting't'ne pH of the .whey by introducing illlfltO the whey a neutralizing agent .in ,quantity sufficient to bring the :pH of said whey -to .a value ofirom approximately 6.0 to 6.6, ad- :justing'the calcium content or" the whey by introducingxrc'alcium .as a salt in quantity sufiicient to :bring thecalcium content, computed ona dry solids basis, to a value of ,from approximately 15% .to 310% .and concentrating the whe to' tween approximately 1.5% and 3.0% to bringthe solid content thereof toa pointof fromapproximately 35% to-approximately 55%, and thereafter heating the concentrated whey .at a temperature approximately 250 F. for a period sufficient to produce insoluble edible proteinaceous :materialrin quantity sufiicient .to impart a pud- "dingeli'ke consistency to the product.

-10..Atnew and :improved whey product possessing the property of imparting to'bread mixes,

wheniused asianingredient thereof, moisture 'absorption and retention properties substantially comparable to those imparted to such bread mixes by milk, when used as *an'ingredient thereof, and

also possessingitheproperty of imparting torfin- "ished bread products,when used as'an ingredient in themixes thereof, volumeiiorthe ingredients employed, texture and body substantially comparable tothe volume for'theingredients employed, .texture, and body imparted to .finishcd bread products when milk is used as. an ingredient in the mixes thereof, made in accordance with the process defined by claim .1.

ll.;-A.new and improvedwhey product possessingthe property of imparting to bread mixes,

whenused as. an ingredient thereof, moisture absorption .and retention properties substantially comparable to those imparted to such bread mixes-by mil-ln when used as an-ingredient thereof, and also: possessing the property of imparting to :finished .bread' products, when used. as an ingredient in they mixes thereof, volumefor the ingredients employed, texture, ,and body, subrstantially:comparablezto the volume "for the ingredients temployed, texture, and :body imparted.

7 5 .to finishedibread products when 'milk ,is' usedas an ingredient in the mixes thereof, made in accordance with the process defined by claim 12.

12. The process of producing a product derived from milk, which comprises concentrating Whey having a pH of from 6.0 to 6.6 and a calcium content, computed on a dry solids basis, of between approximately 1.5% and 3%, and a minor proportion by dry weight of an added protein, to a point where the solids content is from approximately 25% to approximately 55% and thereafter heating the concentrated whey at a temperature of from approximately 200 F. to 280 F. for a period sufficient to produce insoluble edible proteinaceous material in quantity sufficient to impart a pudding-like consistency to the product.

13. The process of producing a product derived from milk, which comprises, without referenceto order, the steps of adding protein to whey having an initial pH of approximately 3.5 to 5.0, introducing into such whey, calcium hydroxide in quantity suflicient to adjust the pH thereof to approximately 6.0 to 6.6, and to adjust the calcium content thereof, computed on a dry solids basis, to between approximately 1.5% and 3.0%, thereafter concentrating the adjusted and protein-enriched whey to a point where thesolids' PAUL FRANCIS SHARP. DAVID D. PEEBLES.

LE ROY RAYM'OND HAWK.. ARTHUR M. BESEMER.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,023,014 Flanigan Dec. 3, 1935 2,181,146 Peebles et a1. Nov. 28, 1939 2,188,907 Lavett Feb. 6, 1940 2,336,634 Peebles Dec. 14, 1943 OTHER REFERENCES U. S. Dept. Agriculture Circular (No. 549, cited, page 90.

Food Industries, vol. 13, No. 11, Nov. 1941, pages 36 to 38 and 96. 

1. THE PROCESS OF PRODUCING A PRODUCT DERIVED FROM MILK WHICH COMPRISES, CONCENTRATING A WHEY HAVING A PH OF FROM 6.0 TO 6.6 AND A CALCIUM CONTENT, COMPUTED ON A DRY SOLIDS BASIS, OF BETWEEN APPROXIMATELY 1.5% AND 3.0%, TO A POINT WHERE THE SOLIDS CONTENT IS FROM APPROXIMATELY 25% TO APPROXIMATELY 55%, AND THEREAFTER HEATING THE CONCENTRATED WHEY AT A TEMPERATURE FROM APPROXIMATELY 200* F. TO 280* F. FOR A PERIOD SUFFICIENT TO PRODUCE INSOLUBLE EDIBLE PROTEINACEOUS MATERIAL IN QUANTITY SUFFICIENT TO IMPART A PUDDING-LIKE CONSISTENCY TO THE PRODUCT. 